Abstract: The NBW-A-1000 biomass combustion and post-treatment analysis test system was used to measure the emission characteristics of SO₂ and NO in microalgae and sawdust molding fuels online at different temperatures and ratios of mixed combustion.The instantaneous emission concentrations of SO₂ and NO and the conversion rates of S and N under different conditions were analyzed.The results showed that compared with microalgae,the peak concentration of SO₂ and NO in the combustion of sawdust was very small,and the peak of precipitation appeared later.As the proportion of mixed microalgae increased,the amount of SO₂ and S conversion increased.The production amount of NO and the conversion rate of N first increase and finally stabilize.When the mixed molding fuel is burned at 600-900 ℃,the instantaneous concentration curves of SO₂ and NO precipitation have a single peak structure,and the temperature reaches 900-1000 ℃.The instantaneous concentration curve of SO₂ and NO precipitated into a bimodal structure,and the S conversion rate continued to rise as the temperature increased.According to the emission standard of biomass forming fuel pollutants,combined with the requirements of combustion quality,the optimum microalgae ratio and combustion temperature of microalgae and wood chips mixed fuel are 10% and 800 0 C respectively,and the instantaneous concentration of SO₂ and NO is precipitated under this condition.The peak values are 36.8 mg/m3 and 90.80 mg/m3,respectively.